Manufacturers of tobacco products are continually striving to find more economical ways of utilizing the various smoking materials comprising the products. For example, considerable effort is being made to increase the physical size of tobacco in various forms through expansion processes, such as steaming and rapid heating of tobacco containing readily volatizable agents. Such expansion processes not only provide the tobacco with increased fill power, but also provide a viable way of reducing and controlling the delivery of the various smoke constituents.
Reconstituted tobacco or tobacco substitute materials in sheet form may also be expanded for the advantages enumerated above. It has also been found that sheet smoking materials may be crimped, generally into strip form, to provide increased fill value. Crimping prevents the strips from settling or packing together due to the geometric configuration. Cigars and cigarettes filled with crimped smoking material are characterized by being firmer, yet provide the manufacturer with increased yield of product for a given weight of smoking material or, in other words, increased fill value.
There are a number of techniques described in the prior art for crimping smoking materials. For example, according to U.S. Pat. No. 1,647,694, crimped strips may be produced from a compacted mass of tobacco leaves by cutting the mass with an appropriately shaped edge into strips having a shape similar to the cutting edge. The patentee alleged that an increase in filling value of up to 10% can be obtained into products made from the strips. Obviously, it is the geometry of the strips which provides the increased fill value.
Other prior art apparatus and process employ shaped rollers which crimp already severed strips into the desired shape. Still other techniques for shaping strips are employed, such as cutting strips, which are bent, obliquely across the bend, thereby providing the strips with a crimp in the plane of the strip.
No entirely satisfactory method has been devised, however, which provides manufacturers with simple process and apparatus for crimping strips of tobacco material. The prior art is replete with complex mechanisms and/or processes for shaping tobacco materials. It is, therefore, a paramount object of the present invention to provide for simple apparatus and method for manufacturing crimped strips of tobacco smoke material.